Heat exchanger for motor vehicles

ABSTRACT

The invention relates to a heat exchanger for motor vehicles, for example a charge air cooler or cooling liquid cooler, composed of tubes ( 1 ) which are formed from in each case two plates ( 1   a,    1   b ) and have two opposite longitudinal sides (L 1 , L 2 ) and two opposite narrow sides (S), with one of the longitudinal sides (L 1 ) constituting the inflow side (A) for cooling air, for example, and composed of heat transfer fins ( 2 ) or the like which are arranged between the tubes ( 1 ) and through which the cooling air flows freely, and composed of collecting spaces ( 3 ) which are formed on the ends ( 4   a,    4   b ) of the tubes ( 1 ) or of the plates ( 1   a,    1   b ), characterized in that at least the one end ( 4   a ) of the tubes ( 1 ) opens out in the longitudinal side (L 2 ) which is remote from the inflow side (A), and in that the other end ( 4   b ) of the tubes ( 1 ) either likewise opens out in the remote longitudinal side (L 2 ) or in the longitudinal side (L 1 ) which forms the inflow side (A) or in one of the narrow sides (S). The heat exchanger has comparatively large heat transfer faces.

CROSS-REFERENCE TO RELATED APPLICATIONS

Priority is hereby claimed to German Patent Application No. DE 10 2006 019 024.6, filed Apr. 25, 2006 and to International Patent Application PCT/EP2007/002271, filed Mar. 15, 2007, the entire contents of each of which is incorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to a heat exchanger (e.g., a charge air cooler or cooling liquid cooler) for motor vehicles and can include tubes which are each formed from two plates and have two opposite longitudinal sides and two opposite narrow sides, with one of the longitudinal sides constituting the inflow side for cooling air, for example, and composed of heat transfer fins or the like which are arranged between the tubes and through which the cooling air flows freely, and composed of collecting spaces which are formed on the ends of the tubes or of the plates. The invention also relates to a cooling module for motor vehicles.

BACKGROUND

DE 30 17 701 describes conventional heat exchangers. In said document, the plates are of approximately rectangular design. The collecting spaces are formed by apertures which are arranged in the plates and are formed at the opposite ends of the plates. The two plates which together form one tube are for this purpose stacked congruently one over the other with their apertures aligned. The heat transfer fins are placed into the spacings between the tubes. The cooling air then flows freely through said spacings.

In comparison to other and possibly most heat exchangers of the type which have collecting tanks at the ends of flat tubes (DE 197 02 183 A1)—that is to say at the opposite narrow sides of tubes—the spatial requirement of the heat exchanger was therefore reduced. The collecting tanks require installation space which is not available for heat transfer. However, in the heat exchanger from DE 30 17 701, there is likewise no effective heat transfer in the region of the collecting spaces.

For this reason (installation space), in DE 197 02 183 A1, the collecting tanks were designed to be as flat as possible, as shown in FIG. 1 of said document by the reference symbol 22. In said heat exchanger, therefore, the heat exchanger network composed of flat tubes and corrugated fins can be configured to be slightly larger for the same installation space.

Another heat exchanger whose tubes are likewise formed from in each case two plates is known from DE 44 07 080 A1. Said heat exchanger could indeed be used as a charge air cooler. It is however of a different generic type, that is to say the generic type in which the plate stack which forms the tubes is arranged in a housing. In said heat exchanger, the charge air flows in at one side of the housing, is in heat-transferring contact with a cooling liquid which flow in the tubes, and leaves the housing at the opposite side.

Further prior art can be gathered for example from DE 103 28 638 A1 and from DE 103 59 806 A1. The heat exchanger shown and described in said documents are of a similar generic type, that is to say a generic type which is likewise not freely traversed by a coolant. Said documents describe in particular exhaust gas heat exchangers in which both the ducts for the exhaust gas and the ducts for a cooling liquid are formed by the configuration of the plates. The two media thus flow within the ducts formed by the specific plate configuration.

Finally, reference should also be made of a further heat exchanger which is shown and described in DE 40 12 046 A1. Said heat exchanger is of the type in which cooling air can flow freely through the heat transfer fins. In said heat exchanger, the ends of flat tubes have been bent around and attached directly to one another. Collecting tanks can be attached to the ends. The bending region or the attachment region of the collecting tanks in said heat exchanger is likewise not available for heat transfer.

SUMMARY

In some embodiments, the object of the invention is that of providing comparatively large heat transfer faces in a heat exchanger of the generic type described in the introduction. The features of the present invention, as described in more detail below, can lead to the achievement of said object.

Because preferably both ends of the tubes open out in the longitudinal side which is remote from the inflow side, and which therefore faces away from the cooling air flowing in, it is possible to form the entire area of the heat exchanger which has air flowing in, or at least a relatively large part thereof, as a heat transfer face, resulting in the heat transfer face being comparatively enlarged. It was possible to provide the enlargement of the heat transfer faces despite the collecting tanks which are also arranged on the ends of the tubes of the heat exchanger according to the invention. The far ends of the plates or of the tubes are preferably slightly enlarged in cross section and bear against one another with their narrow sides. The collecting tanks can thereby be attached without the provision of a tube base. If the cross-sectional enlargement of the far ends is to be dispensed with, tube bases must be attached to the ends of the tubes to which the collecting tanks are to be fastened.

It is possible to have only one end of the tubes open out in the longitudinal side which is remote from the inflow side, and to provide the other end of the tubes on the narrow side which is remote from the opening-out point.

Because at least one end of the tubes opens out at a longitudinal side, the geometry or the configuration of the plates is accordingly not rectangular as in the prior art but is for example L-shaped, U-shaped or Z-shaped.

Another exemplary embodiment which is similar to the exemplary embodiment with U-shaped plates has plates or tubes whose configuration has a convex contour. The contour is arched in the direction of the inflow side.

In each case two plates are attached with their edges to one another in order to form a tube. The plates can be identical. Both plates then have an upright edge at which the two plates bear against one another and are connected in order to form the tube. It is however also possible to make one plate approximately planar, that is to say to form said plate without an upright edge, and to provide the other plate with an upright edge. It is also possible to place the upright plate edges into one another in order to connect them.

The ends of each of the tubes or plates have, as already indicated above, one angled contour in order to be able to open out in a corresponding longitudinal side.

The angled contoured piece can be kept very short—specifically long enough in order to be able to attach collecting tanks thereto.

Heat transfer fins or other elements which promote the transfer of heat are inserted between the tubes. Elements of said type are also arranged in the region with the angled or curved contour.

In an application as a charge air cooler, inserts for turbulence generation are situated in the tubes. It is also possible here, however, to provide other formations, such as deformed portions or the like, which act in the same direction. Said connection of the plates and the connection of the plates or of the tubes to the heat transfer fins is preferably carried out by means of a soldering process. The collecting tanks can be composed of plastic or of metal.

Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is now explained in some exemplary embodiments on the basis of appended drawings. Said explanations can contain further features and advantages. The figures show the following:

FIG. 1 shows a perspective view of a heat exchanger according to a preferred exemplary embodiment;

FIG. 2 shows a view of a tube piece;

FIG. 3 shows a view of a plate piece;

FIGS. 4-6 show other views of the heat exchanger from FIG. 1;

FIGS. 7 and 8 show views of a cooling module with a heat exchanger; and

FIGS. 9-11 show structural illustrations of heat exchangers in other exemplary embodiments (views from above or from below).

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings.

The heat exchanger shown in the exemplary embodiments is used in a motor vehicle. Said heat exchanger can be either a liquid cooler which is impinged on by cooling air or else a charge air cooler. Other applications, such as, for example an oil cooler which is impinged on with cooling air, are likewise entirely conceivable. The heat exchanger shown in FIG. 1 in a perspective view is arranged at the front of a motor vehicle. Said heat exchanger has a comparatively large inflow face A which can be impinged on with cooling air. In the preferred exemplary embodiment, both ends 4 a and 4 b of the plates 1 a, 1 b or of the tubes 1 are situated at that longitudinal side L2 of the plates 1 a, 1 b or of the tubes 1 which is remote from the inflow side A. It is therefore also possible in the case of the preferred exemplary embodiment to refer to approximately U-shaped plates 1 a, 1 b which are used there. In each case one collecting tank 30 is situated at those ends 4 a and 4 b of the plates 1 a, 1 b which are practically also the free ends of the “U” (FIGS. 4-6). The collecting tanks 30 are either made from plastic and are mechanically fastened to the ends 4 a and 4 b or are, like the tubes 1 and the heat transfer fins 2 arranged between the tubes 1, made from metal. Here, aluminum or a suitable aluminum alloy is the preferred choice. The plates 1 a, 1 b have an upright edge 10 and are in each case placed together to form a tube 1 in order to (later) be soldered at their upright edges. FIG. 2 shows a piece of the tube with one end 4 and FIG. 3 shows a piece of a plate 1 a. The plates 1 a and 1 b are substantially identical. The tubes 1 are placed together with the heat transfer fins 2 in a conventional manner. Here, heat transfer fins 2 or other formations which improve the transfer of heat are inserted or arranged in the plate regions 5 which are angled and lead to the collecting tanks 30. The heat exchanger block thus formed is subjected to a hard soldering or brazing process and thereby joined together to form a compact block. It can be seen from FIG. 4 that, in said exemplary embodiment, inserts 20 are also situated within the tubes 1. The inner inserts 20 need not extend over the entire tube length. Said inner inserts 20 can also have a spacing with respect to the narrow sides S.

Said longitudinal sides L1, L2 preferably run in the transverse direction of the motor vehicle (not shown). Said longitudinal sides can however also run in the vertical direction of the motor vehicle.

FIGS. 9, 10 and 11 show further possible exemplary embodiments in views of the heat exchanger, from above or from below, which likewise have enlarged heat transfer faces. Said figures are diagrammatic illustrations. The exemplary embodiment as per FIG. 9 has approximately Z-shaped plates 1 a and 1 b which form in each case one tube 1. The left-hand end 4 a of the plates 1 a, 1 b or of the tubes 1 in the figure opens out into that longitudinal side L2 which is remote from the inflow side A. The other end 4 b, which is at the right-hand side in the figure, opens out in the inflow side A or in the longitudinal side L1.

FIG. 10 could be considered to be an exemplary embodiment which has slightly larger heat transfer faces than that according to FIG. 9. In said exemplary embodiment, use is made of L-shaped plates 1 a, 1 b or tubes 1. The left-hand end 4 a of the plates 1 a, 1 b or of the tubes 1 in the figure opens out, as in FIG. 9, into that longitudinal side L2 which is remote from the inflow side A. The other end 4 b is situated in the narrow side S which is remote from the left-hand end 4 a. Here, the collecting tank 30 which is arranged there is of particularly flat design so that it is not necessary to significantly restrict the size of the inflow side A.

A further exemplary embodiment which is not shown has a collecting tank 30 which is arranged not at the remote narrow side S but at the near narrow side S. In said case, the tubes 1 have a flow division in the longitudinal direction, so that the charge air, for example, which flows therein can flow to the remote narrow side S and back from there again.

The exemplary embodiment according to FIG. 11 is similar to that of FIGS. 1-6. Said exemplary embodiment has, however, a convex contour of the longitudinal sides L1 and L2. It is also possible here for the entire area of the plates 1 a, 1 b to be formed as a heat transfer face. In comparison to known ring coolers in which the flat tubes are bent by means of their narrow sides S, which is still difficult in production terms, in particular if there are inserts in the flat tubes, the proposal serves to improve or facilitate producibility. In FIG. 11, the longitudinal sides L1, L2 diverge slightly toward the ends 4 a, 4 b and apparently enlarge the cross section of said ends 4 a, 4 b. This is not preferred but is owing to the production by means of “auto forming”. The longitudinal sides L1 and L2 which are provided with the convex contour preferably run parallel to one another, that is to say also at the ends 4 a, 4 b. The collecting tanks 30 at the ends 4 a, 4 b have merely been indicated.

FIG. 7 now shows a view of the inflow side of a cooling module in which the heat exchanger according to FIGS. 1-6 is situated. In the exemplary embodiment, the heat exchanger is a charge air cooler LLK. The inflow side of the cooling module is at the same time the inflow side of the heat exchanger. The heat exchanger has been arranged in the lower region of the cooling module. Situated above said heat exchanger are for example a cooling liquid cooler and other components relating to cooling modules. FIG. 7 makes particularly clear the enlarged heat transfer face of the charge-air cooler LLK in comparison with the cooling liquid cooler arranged above. FIG. 8 shows the cooling module from the rear side. The inlet and outlet connecting pipes of the charge air cooler LLK can be seen to the left and right at the bottom. The entire area is enclosed by a ventilator cowling V on which a fan is arranged in order to suck cooling air through the cooling module.

Various features and advantages of the invention are set forth in the following claims. 

1. A heat exchanger for motor vehicles, for example a charge air cooler or cooling liquid cooler, the heat exchanger comprising: a plurality of tubes, each of which is formed from a pair of plates and has two opposite longitudinal sides and two opposite narrow sides, with one of the longitudinal sides constituting an inflow side for cooling air and composed of heat transfer fins arranged between the tubes and through which the cooling air flows freely, and composed of collecting spaces which are formed on the ends of the tubes or of the plates, wherein at least the one end of the tubes opens out in the longitudinal side which is remote from the inflow side, and in that an other end of the tubes either likewise opens out in the remote longitudinal side or in the longitudinal side which forms the inflow side or in one of the narrow sides.
 2. The heat exchanger according to claim 1, wherein a collecting tank which forms the collecting space is attached to each end.
 3. The heat exchanger according to claim 1, wherein both ends of the tubes open out in the longitudinal sides, and wherein collecting tanks are arranged at both ends.
 4. The heat exchanger according to claim 1, wherein both ends of the tubes open out in the longitudinal side which is remote from the inflow side of the cooling air, and wherein collecting tanks are attached to both ends.
 5. The heat exchanger according to claim 1, wherein that end of the tubes or of the plates which opens out in one longitudinal side has at least one of a bent, curved and angled contour.
 6. The heat exchanger according to claim 1, wherein the heat transfer fins are also arranged between the tubes in the regions which have the angled contour.
 7. The heat exchanger according to claim 1, wherein the plates which form the tubes are configured to be of one of approximately L-shaped, approximately U-shaped, and approximately Z-shaped form.
 8. The heat exchanger according to claim 1, wherein the configuration of the plates which form the tubes has a convex contour.
 9. A cooling module for motor vehicles, the cooling module comprising: a plurality of tubes, each of which is formed from a pair of plates and has two opposite longitudinal sides and two opposite narrow sides, with one of the longitudinal sides constituting an inflow side for cooling air and composed of heat transfer fins arranged between the tubes and through which the cooling air flows freely, and composed of collecting spaces which are formed on the ends of the tubes or of the plates, wherein at least the one end of the tubes opens out in the longitudinal side which is remote from the inflow side, and in that an other end of the tubes either likewise opens out in the remote longitudinal side or in the longitudinal side which forms the inflow side or in one of the narrow sides.
 10. The cooling module according to claim 9, wherein a collecting tank which forms the collecting space is attached to each end.
 11. The cooling module according to claim 9, wherein both ends of the tubes open out in the longitudinal sides, and wherein collecting tanks are arranged at both ends.
 12. The cooling module according to claim 9, wherein both ends of the tubes open out in the longitudinal side which is remote from the inflow side of the cooling air, and wherein collecting tanks are attached to both ends.
 13. The cooling module according to claim 9, wherein that end of the tubes or of the plates which opens out in one longitudinal side has at least one of a bent, curved and angled contour.
 14. The cooling module according to claim 9, wherein the heat transfer fins are also arranged between the tubes in the regions which have the angled contour.
 15. The cooling module according to claim 9, wherein the plates which form the tubes are configured to be of one of approximately L-shaped, approximately U-shaped, and approximately Z-shaped form.
 16. The cooling module according to claim 9, wherein the configuration of the plates which form the tubes has a convex contour. 